1. Field of the Invention
Apparatus for generating electrical power by extracting energy from ocean waves.
2. Description of the Prior Art
A preponderant number of prior art concepts aimed at producing useful electrical power from the vertical motion of ocean waves, of which applicants are aware, have involved the use of floats, either to produce a mechanical generator-operating action through gearing or the like, as in Masuda U.S. Pat. No. 3,204,110, for example, or to compress atmospheric air entrapped above the wave crests to operate an air motor driving the electric generator, as in Corbett Jr. et al U.S. Pat No. 3,064,137, for example.
One apparatus, however, as disclosed in a Semo U.S. Pat. No. 3,353,787 is based on a closed hydraulic system employing an array of submerged fixed-position tubes extending parallel to a shoreline and having flexible upper surfaces for downward deflection by overhead wave pressure to displace hydraulic fluid into a collecting conduit leading to a shore installation that includes an accumulator, a hydraulic motor for generator operation, and a return sump at exit to the motor. Return flow of hydraulic fluid to the submerged tubes is intended to occur via the above collecting conduit. A check valve at each tube permits facile egress of fluid from such tube and a restricted port through each check valve is intended to permit slow return flow to each tube for refilling.
While a submerged closed-circuit power generating system of the fixed-position flexible-wall fluid-displacing type can have the advantage of allowing the ocean surface to remain unobstructed while at the same time affording a breakwater action for shoreline protection, the practical operability of the Semo apparatus is questionable with respect to displacement of hydraulic fluid by wave-created subsurface pressure variation, as well as with respect to the facile-egress restricted-return flow to and from the tubes imposed by the choked check valves in such Semo system.